Poison Ivy

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Introduction

Poison ivy can grow as a plant, bush, or vine.  Sap from the plant causes the skin reaction.  Although itchy and annoying, most poison ivy rashes are not serious.  However, the symptoms are bothersome enough that you should remember the rhyme, “Leaves of three, let it be,” meaning, stay away from the plant with the telltale three leaves.
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Anatomy

Your skin covers your body and protects it from the environment.  Poison ivy sap (urushiol) is an oily resin that upon contact with the skin causes a skin reaction (contact dermatitis).
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Causes

Contact between the sap from the poison ivy plant and the skin causes an adverse reaction in the form of a rash.  You may come in contact with the sap directly from contact with the plant or from sap in the air, on pet fur, or objects such as gardening tools, sport equipment, blankets, or jackets.  Poison ivy can remain on stored items and activate a rash if touched even after a year.
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Symptoms

Poison ivy causes a red itchy rash within a few days of contact with the sap.  The rash may contain small bumps, blisters, or swelling.  Scratching may cause the blisters to open and ooze. 

A poison ivy rash may last up to about three weeks.  The rash itself is not contagious, but it can be spread by continued contact with the sap. 
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Diagnosis

You should contact your doctor if your poison ivy rash is severe, widespread, or on a delicate area, such as the genitals, eyelids, or mouth.  You should also contact your doctor if your skin becomes infected, you develop a fever greater than 100°, or if your rash lasts longer than a few weeks.  Your doctor can diagnose a poison ivy rash by looking at your skin.  A culture may be taken to check for a skin infection.
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Treatment

Most poison ivy rashes are treated with over-the-counter soaps, lotions, creams, and sprays that are formulated to ease symptoms.  Your doctor may prescribe a corticosteroid medication.
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Prevention

There are several steps you can take to help prevent a poison ivy rash:

• Gently wash your skin within 5 to 10 minutes of contacting the sap.
• Wash any items that have poison ivy sap on them.  Dry cleaning will also remove sap.
• Remove poison ivy plants from your yard.  Ask your local gardening store about specific products.
• Do not burn poison ivy plants.  The sap can be carried in smoke and inhaled.
• When outdoors, make sure to stay on clear paths.  Keep your children and pets from wooded areas.
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Complications

Severe life-threatening reactions can occur if the poison ivy sap is swallowed or inhaled. 
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This information is intended for educational and informational purposes only. It should not be used in place of an individual consultation or examination or replace the advice of your health care professional and should not be relied upon to determine diagnosis or course of treatment.

The iHealthSpot patient education library was written collaboratively by the iHealthSpot editorial team which includes Senior Medical Authors Dr. Mary Car-Blanchard, OTD/OTR/L and Valerie K. Clark, and the following editorial advisors: Steve Meadows, MD, Ernie F. Soto, DDS, Ronald J. Glatzer, MD, Jonathan Rosenberg, MD, Christopher M. Nolte, MD, David Applebaum, MD, Jonathan M. Tarrash, MD, and Paula Soto, RN/BSN. This content complies with the HONcode standard for trustworthy health information. The library commenced development on September 1, 2005 with the latest update/addition on February 16, 2022. For information on iHealthSpot’s other services including medical website design, visit www.iHealthSpot.com.